Example 4: 3-D RC frame subjected to earthquake base excitation

Created by: Quan Gu (Xiamen University, China), Joel P. Conte (UCSD), Michele Barbato (LSU), Yong Li (UCSD)

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This example is taken as a 3-D three-story reinforced concrete frame structure with rigid diaphragm behavior at each floor, subjected to bidirectional earthquake base excitation with ground acceleration time histories taken as the two horizontal components of the 1978 Tabas earthquake.

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Figure 1 3-D one-bay three-story reinforced concrete building: structural model and input ground motion

To run this example, the user needs to run Example4_Frame3D.tcl in OpenSees to perform FE response and response sensitivity analysis. To verify the DDM results using forward finite difference analysis, the user needs to run Example4_Frame3D_FFD.tcl. Finally, the user needs to run in Matlab the file Example4_cmp.m to visualize the results.

Figure 2 Response of 3-D building: moment-curvature hysteretic response about the x-axis at Section 1 (see Figure 1)

Figure 3 Validation of DDM results for 3-D building through forward finite difference analysis: normalized sensitivity of first interstory drift in the x-direction to core concrete strength fc

Figure 4 Validation of DDM results for 3-D building through forward finite difference analysis: normalized sensitivity of first interstory drift in the x-direction to core concrete strength fc (zoom view)

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Tcl Input File Download

To execute this ananlysis in OpenSees the user has to download this input file:

• Media:Example4.zip

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Reference:

Gu Q., Barbato M., Conte J.P. (2009) “Handling of Constraints in Finite Element Response Sensitivity Analysis.” Journal of Engineering Mechanics (ASCE), 135(12):1427-1438.